To stabilize a bone fracture using an inflatable device, such as an inflatable intramedullary nail, the inflatable device may have to maintain a certain pressure for an extended period of time, which may include the duration of implantation. If such a pressure is not maintained, the bone fracture may not heal or it may malunion. Many things may affect the pressure in this closed system, which may include the inflatable nail and fracture cavity. For example, after a fracture is set and the inflatable device is sealed off during implantation, any expansion of the intramedullary canal or leakage from the device may cause the system pressure to drop. In another example, even slight expansion of an inflatable balloon nail or small losses of fluid at joints or bonds may influence the system pressure. If a system having no stored energy incurs such pressure losses, the pressure may drop immediately.
Thus, it may be advantageous to provide stored energy in an accumulator, which may supply energy, absorb pressure spikes, and stabilize a system during changes in fluid or cavity volume. The use of an accumulator may result in a system that is able to withstand greater volume losses or changes with a reduced effect on the system pressure. Such an accumulator may be located inside or outside an inflatable nail.